Description from Flora of China
Rhizome very short, ligneous. Culms densely tufted, 25-50 cm tall, obtusely trigonous, smooth, clothed with bladeless sheaths at base. Leaves many, nearly basal, shorter or slightly longer than culm, blades 3-8 mm wide, stiff, smooth on both surfaces, scabrous on upper margins, margins revolute; sheaths 3.5-8 cm, eventually splitting. Involucral bracts leaflike, surpassing subtending spikes, sheathed. Spikes numerous, usually 5-9 borne in an involucral bract sheath, sometimes ramose and disposed in a panicle, androgynous, female part and male part subequal or female part slightly longer, oblong or oblong-cylindric, sometimes narrowly ovate, 10-25 × ca. 5 mm, densely many flowered; lower peduncles slender, upper rather short. Female glumes pale yellow, ovate-lanceolate, ca. 4 mm, mem- branous, 1-3-veined, margins white hyaline, apex attenuate, mucronate or muticous. Utricles yellowish green, nearly horizontally patent or obliquely patent at maturity, shorter than or equaling glume, elliptic or ovate-elliptic, trigonous, ca. 3.5 mm, membranous, glabrous, 5-veined, 2 lateral veins distinct and others inconspicuous, base subrounded, estipitate, apex attenuate into a ± long beak, orifice shortly 2-toothed. Nutlets dark brown, tightly enveloped, broadly ovate, trigonous, ca. 1.2 mm, base estipitate; stigmas 3. Fl. and fr. Apr-May.
● Among rocks, ravines; 1300-2700 m. C Yunnan (Kunming).